Britain's fertility research watchdog has given the green light to therapeutic cloning.

The Human Fertilisation and Embryology Authority has announced that the Newcastle Centre for Life will be granted a licence to create human embryonic stem cells using cell nuclear transfer.

The regulatory body said that stem cells created under the licence will be used for research purposes only.

Pro-life campaigners warned that Britain will "regret giving approval to the unethical, dangerous and unnecessary practice".

But the HFEA said it was an important area of research and a "responsible use of technology".

The licence will allow scientists to create human embryos by inserting the nuclei from human skin or stem cells into human eggs.

Current laws allow research if it meets strict criteria such as advancing the treatment of infertility or increasing knowledge about serious disease.

The HFEA said the new research would aim to "increase knowledge about the development of embryos and enable this knowledge to be applied in developing treatments for serious disease".

While the research is preliminary and not aimed at specific illnesses, it is hoped that it will prove the foundation for further development in the treatment of serious disease.

"After careful consideration of all the scientific, ethical, legal and medical aspects of the project, the HFEA licence committee agreed to grant an initial one year research licence to the Newcastle Centre for Life," confirmed HFEA chairman Suzi Leather.

"This is an important area of research and a responsible use of technology. The HFEA is there to make sure any research involving human embryos is scrutinised and properly regulated."

Reacting to the news, the Society for the Protection of Unborn Children warned of the "dangers" of therapeutic cloning.

"Human cloning is dangerous because it will lead to so-called reproductive cloning," said political secretary Anthony Ozimic.

"Like other areas of embryo experimentation, human cloning is likely to produce none of the promised medical benefits, but it will lead to the birth of cloned babies - possibly on a vast scale.

"Human cloning is unnecessary because adult stem cell research, a rapidly advancing ethical alternative to embryo experimentation, is already providing treatments for the very same diseases that pro-cloning scientists claim to be interested in treating.

"Even in the unlikely event that experiments on embryos did prove to have some beneficial effect, it would still be unacceptable to use human beings in this way."